I realize that radiator misters are not the best solution to heating problems. Like in my situation, I had the radiator rebuilt to the largest core the tank and size would allow, and still had heating issues if the outside temp was over 90 degrees. I installed 15 misters from Home Depot, and while it helped, I still had to be gentle on up hills and stopping to let it cool-albeit it would cool off in less then 5 minutes.This summer, I experimented and drilled out two of the misters on the bottom with a 1/16" drill. I had the misters aimed out and they squirted about 15ft out from the bus! After re-aiming them, the results were dramatic. I pulled the big hill going up to Shaver Lake in 90 degree weather and didn't have to stop! I think it flows about a gallon a minute.

The formula for water evaporation is 1lb of water evaporating is 1,000btu's. So one gallon per minute would be 8,300btu/minute, or 498,000btu's of heat rejection per hour. Now that's some heat dissipation. Whenever you read of what an engine puts out for btu heat rejection, it is always in btu/minute. I know the Allison transmission can put out up to 20,000btu/minute in torque converter mode.

For those that have tried everything but are still getting heating issues, maybe try my trick of drilled out misters, or just plainly install one lawn sprinkler. Good Luck, TomC

Although from a purist point of view, misters are not an ideal solution, very few solutions are. If I want a bus, ideally I would spend the million or so and have an ideal coach. I could also hire a mechanic to run along side too. I guess that's the difference between here and the afterlife.

Just be sure and use distilled water in the misters as regular water will lime up the exterior of the cooling fins and compound the problem. I think some guys have stated that they used a condensor cleaner that heating and air places have. After Jack Conrad's advise I installed a seperate tranny cooler and also added a 24 volt fan. It really puts out some heat!!

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Seven Heaven.... I pray a lot every time I head down the road!!Bad decisions make good stories.

I have never examined any mister system up close, but I have read where some said that RV type mister system worked substantially better than most homemade ones. I think the concept is to cool the air as a swamp cooler does rather than just wetting down the radiator.

Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

Our mister system works well now. In the beginning we had calcium issues, but we found a filter that chemically eliminates the calcium. Since then (5yrs.) we've had no issues with buildup on the fins, or plugged misters. We use an automotive fuel pump the push the water through the filter and the misters. It's a fine mist near the top and middle of the rad. The biggest difference is on slow inclines. For the passes I just use a lower gear and crawl. I also have a 4 speed manual instead of an automatic which means a lot less heat to deal with...Cable

Spraying water on a radiator increases it's cooling capacity because of the energy dissipated by the phase change of the water from liquid to gas. In high humidity, the misters wouldn't lower the air temp much, but would still have a big impact on the engine temp.

Misters are a cheap solution that can temporarily get you out of a jam, but, for the long term, I'd rather have additional coolers (to take the transmission & engine oil cooling loads off the radiator) & add a remote mounted auxiliary radiator if needed.

But, that's just me. . . .

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I know you believe you understand what you think I said, but I am not sure you realize that what you heard is not what I meant. (R.M. Nixon)

I know guys that love the HD patio misting systems they own radiator shops ,the fan sucking water through the radiator at 20 to 30 MPH destroys a radiator but radiators are 2 to 3 grand and a engine is around 12 grand on the average it is your call but I never had mister system.

well when it rains acid rain it's worse than any distilled water! When we run in the hills it might be on 1-2 mins at a time, with 18 tips running we use about 3-4 gals a day (revised down from an old estimate of 10) ..takes about 1 min to drop the temp 20*......it does make a little mess back there but then again every time we take the bus out it seems to rain somewhere during our trip

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Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

I still have my otr heat I also have a switch to turn off the power to the heat controll valve (defalt is full heat) When pulling a hard grade if temp start to rise. Flip the switch and turn the heat on Temp comes right down. Some times it gets warm in the coach but the DD stays cool. Some day I will cut into the heat duct and open it to the old otr ac compartment (MC-8) But until then only the occupants get warm and that cost less than new 8V71 works for me KISS (Keep it simple stupid) LOL Or just take my foot out of it and enjoy the ride

Steve, check with a shop have you ever wondered why a radiator rots faster in wet areas here in the west nothing to see a radiator 25 years old you won't see that in a wet area where you get a lot rain

luvr I agree about the wet areas compared to the dry areas. Absolutely! But in a system like this, wouldnt the water evaporate so quickly that nothing has a chance to get wet and stay wet? And it would be used only very infrequently.

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The Little GTO is a 102" wide and 40' long 1983 GMC RTS II and my name is Teresa in case I forgot to sign my post

I thought most of the damage was from salt.....we have some flaking of the fins,came to us that way.... this bus was parked in Utah for at least 3 years prior to that sat in a probate issue for at least 7 more....anyway we need a rodding or core...plan to work on it this fall after hurricane season....we're back in fl. now

« Last Edit: September 10, 2010, 06:10:27 PM by steve wardwell »

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Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

Dumb question-why would this be any different than driving in rain? I read post again and still don't get it...I don"t have the problem so don"t have misters.. is it true of all radiator material? copper/alum or copper/copper

Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

Most of you know that I have fought a cooling problem on my charge air cooler which is located on the passenger side. I tried 4 electric fans and they did not do the job EXCEPT when we had rain

Lately, I have converted to a hydraulic fan and the helped a bunch, but I still have a problem going up big hills with the potent Series 60. BTW, I do not have a problem with coolant temperature.

To help keep the intake air at less than 150-160 degrees, I have played with misters. There are two schools of thought. One theory is that you spray the incoming air and let the cooler air do a more efficient job. The second theory is that you flood the radiator with water. I tried all kinds of spray heads including some neat heads that are intended to cool chicken houses.

On a recent trip I wanted to try a different head that flowed quite a bit of water. We were parked in a Wal Mart and I walked across the street to an ag supply store. I was sure that I would find a good spray head. Nothing. Then the light went on. I use a special spray head from the racing industry on my fire suppression system. Three heads flow 2.25 gallons in 45 seconds. That works out to about a gallon per minute per head. I installed two heads roughly aimed at the charge air cooler. The heads are hooked up to the house water system. I control the heads with a solenoid valve controlled by a switch on the dash.

I played with the system on the way home where we have to go up some darn steep, long climbs out of Denver. I would hit the switch for about 4-5 seconds and then about 30 seconds later repeat the the short burst. I watched the air inlet temperature on the SilverLeaf and the effect was dramatic. You could watch the temperature drop fairly quickly if the boost was not full on and the temperature held with full boost.

Yes it is a band-aid, and yes, I might have some deposit, but I really don't want to damage this engine.

I like the idea of a filter. Might plumb mine through our dual element drinking water filter, or perhaps install a second filter.

Dumb question-why would this be any different than driving in rain? I read post again and still don't get it...I don"t have the problem so don"t have misters.. is it true of all radiator material? copper/alum or copper/copper

There are no differences, except for, water from a mister is cleaner than 99% of the rain!

I too, don't understand why some people feel uneasy about spraying water onto their radiators. It's a great concept actually - In an RV, why build a cooling system that won't be used to capacity for 98% of the time, when it's much cheaper to build a smaller system, and use water misters for that 2% of special occasions?

Now, in a commerical linehaul bus/truck, it's a different story all together.

I'll do the rad work to try to solve the prob... if I need a core......... I'll get the 4 or 5 tube (think mines a 3) General rad from the net was 800 for mine and another hun for the next bigger size.... sent to my door in 3 days w/bolts and gaskits.....worth it to me........s......Ps I was using a carbon filter w/reg fla. water and plugged everything up......cleaned w/CLR ...happy now w/RO or distilled water and great sitting all summer no plugging at all..hey I don't even drink fl. water

« Last Edit: September 10, 2010, 06:54:03 PM by steve wardwell »

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Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

Jim, you see the mister installed on lots of OTR trucks but just like you they spray the air to air charger not the radiator in fact Hayden makes one for that purpose and in the rain it is the drop in outside temps that makes the difference. This post got me to thinking so I pulled out a Cat manual on a D6-R it states never spray water on the radiator when the engine is running and hot as damage may occur from water being sucked through the fins. Idle for 5 minutes cool the radiator down then then wash the radiator and never power wash but people do what they need to do,but I am not for band aids myself

Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

Steve, the typical term is charge air cooler. It is also called air to air cooler and other terms. It is used to cool the air after the turbo and before the intake manifold on modern four-stroke engines. Looks like a radiator.

Keep in mind that we are sucking our air from the side of the bus. On a truck, it is being rammed in the front. So traveling at 65mph in the rain-wouldn't that be cramming in alot of rain water into the radiator and engine? I know my truck didn't care.

If I do get some white calcium build up on the radiator, I simply spray CLR on a cool radiator, let it sit for 5 minutes, and then hose off. Works well everytime. Good Luck, TomC

I like my misters (homebrew using garden emitters ). I use the water on board thru a solenoid to a switch near my side control panel in the drivers area. (just turn my water pump on before the climb.)

When heading from Phx up the 17 to Prescott, I use the misters maybe 5 times a year for 10 minutes. Not a big deal for me. I haven't noticed any buildup. I have learned that I really don't need the misters if I can see my exhaust. I keep my foot out of it and keep the black smoke to a minimum. That keeps the heat down. So, I really don't need the misters, but like them for peace of mind.

Last weekend we went camping near Williams (Dog Town Lake area) and the 17 mile uphill climb from Ashfork to Williams was not a problem if I kept the black smoke(heat) to a minimum. It's pretty touchy with an air throttle to keep it clean.

Also keeping the rpm's up ( 1600 or higher ) is real important in hill climbing..

For me, I keep it in 1st and take my time keeping the revs up -- the old girl likes it that way !

We live in the So Cal High Desert. When I bought our '60 '04 GM eleven years ago, I noticed the engine would exceed 200 degrees on steep inclines in warm weather. I would downshift as needed, but once I actually had to pull over to let her cool. That was coming up the backside of El Cajon Pass on a 100+ degree day... Hi temp alarm sounded.

I'd read about the radiator mister idea in Dave Galey's Bus Conversion Bible - and fashioned one of my own - by cleverly swiping two of the little spray heads from my wife's shrub irrigation line in our front yard. (Heh, heh, heh!)

I tapped into the domestic water system and used a universal (JC Whitney - $10.00) automotive windshield washer pump triggered by a spring-loaded (so I don't forget and leave it on indefinitely) switch on the side-dash control panel. Works really well with only two (180 degree pattern) spray heads - if - I dip into it on time. That's the secret for my coach anyway. As I'm building up a head of steam for the upcoming incline (whilst simultaneously fogging all immediate area mosquitoes) I lay into the mister and just keep it wailing away for the entire length of the grade, or at least as needed to keep 'er cool. This is in spite of the fact that the instructions that come with the pump motor say never to hold it on for more than 10 seconds at a time.

Wish I had the part number and supplier for the solenoid NoRivets mentioned in his post (hint-hint!) That would allow for a much better flow and increased reliability, though I've only had to replace the windshield washer pump once so far, and that was just this past July.

In eleven years of heavy use (during summer months only) I have never experienced any problem with calcium buildup on the radiator. This surprises me greatly, as we have extremely hard water here in the High Desert area.

One other thing, as we never consume the water from our domestic tank (only bathe in it) I did not incorporate any type of backflow device into the leg of water system feeding the mister pump. It would be mandatory otherwise, I should think.

Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

showing water tank w/ filter and high loop..........mister loop on rad door

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Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

even with 18 mister tips the pump cycles on only every 10 secs or so for 3-4 clicks then stops............s...........

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Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%

Nice set-up Steve! Makes mine look pretty puny. I guess I must not be generating that much heat.

HCB, I'm in the Antelope Valley, west-side, Quartz Hill area. I once towed a 26' sailboat up and over Walker Pass to Isabella Lake with our bus, so I know where you are. It's nice up there!

Pulling the grade was fun. I eventually ground 'er down into 2nd, got out the knitting needles and tried not to fall asleep. Well, it wasn't hard to stay awake, actually, as the mob of angry and impatient motorists stuck up my behind pretty much made for a symphony of horns...

I helped a friend add misters to his model 10 Eagle. He was worried about forgetting to turn them off, so I used one of those heatlamp timers like they have in motel rooms. It is a small dial that goes up to like 10-15 minutes. It is made for 120v use but the "clock" part is spring loaded so it does not require 120vac to operate. I used a 12 volt sprinkler valve tied into regular water system.

Easy to install and no worries about leaving it on too long.

I have driven the bus many times and it will come from 195 to 180ish in a couple of minutes.

He and I have almost identical buses. His heats up and mine does not... He has a fresh engine, remote trans cooler, and new radiator, where mine has about 400K on inframe. I know I will need to do mine soon but it is not using but about a gallon of oil every 2500 miles and it is running cool. Go figure

thank you this was mostly preexisting until it got dragged down the road last year...oops ! I have a ballcock shutoff before the pump otherwise it drips all day (even with the new high loop...vacuum breaker maybe?)...It's using the old header tank for the rad......irony here because I want to add a header tank back to the rad...I'll install a smaller one elsewhere...I got the misters & barbed Ts on line... theres a big gallon difference between misting and spraying ours are... .05 or .005 crs moment...I can ck if anyone wants the rating is kinda irrelevant at 40 lbs of pressure I can not overstate the importance of using RO or distilled water with these small water stingy tips

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Sometimes the more I think about something the less I think about something. As soon as I save a little money my bus finds out. Why grab a plane when you can take the bus ? If I'm wrong 10% of the time how can the "Queen" be right 100%